The Summer Cover Crop Show + Planting into Residue

Episode Overview

• This episode of Growers Daily covers the benefits, challenges, and practical methods of summer cover cropping, specifically focusing on buckwheat and sunn hemp.
• The host, Jesse Frost, discusses his experience with excessive rain on his farm, harvesting in the rain, crop damage from rot, and how his direct-seeded milpa patch handled the water.
• The episode features two main educational segments: how to use buckwheat as a short-term placeholder and weed suppressor, and how to successfully plant crops directly into a thick cover crop mulch.
• This content is highly relevant to market gardeners, organic farmers, and no-till growers looking to improve soil health, manage weeds, and integrate cover crops into their rotations.

Key Concepts

• Buckwheat as a Fast Placeholder: Buckwheat is an exceptionally fast-growing cover crop that can flower in just 25 to 30 days. This makes it an ideal "placeholder" to protect and enrich the soil when a bed is unexpectedly empty for a few weeks due to crop failure or timing gaps, preventing weed growth and keeping the soil active.
• Weed Suppression through Rapid Growth: While buckwheat may have mild allelopathic properties, its primary strength in weed control comes from its rapid canopy development. By quickly shading out the ground, buckwheat outcompetes emerging weeds, weakening them and making subsequent bed preparation much easier.
• Managing Soil Temperature Under Mulch: Planting into a thick cover crop mulch (like rolled rye) keeps the soil significantly cooler than bare soil or compost mulch. For warm-weather crops like tomatoes, transplanting directly into this cold soil can cause transplant shock; leaving the dug planting holes open to the sun for a day before transplanting helps warm the root zone.
• Sunn Hemp for Nitrogen and Organic Matter: Sunn hemp is a vigorous summer legume that can fix 120 to 140 pounds of nitrogen per acre in just 8 to 12 weeks. It is particularly valuable for sandy soils or areas plagued by root-knot nematodes, as it does not harbor these pests and adds massive biomass to the soil.

Quotes

• At 2:51 - "This is a crop that will flower in about 25 to 30 days if it's planted at the right time... those flowers can be great for beneficials." - Explaining the rapid life cycle of buckwheat and its immediate ecological benefits to the garden.
• At 9:17 - "One thing you can do is you can plant your pathways to a different cover crop than your beds, and that way you can differentiate where the bed is and where the pathway is." - Offering a clever, practical solution to the common problem of losing bed alignment under a thick, uniform cover crop mulch.
• At 12:16 - "One option is simply digging a furrow through the mulch... and sowing something and then covering that back with the mulch." - Explaining how to hand-seed larger crops like beans or garlic into a heavy residue without specialized tractor equipment.

Takeaways

• Terminate buckwheat within 10 to 14 days of flowering to prevent it from dropping seed and becoming a persistent weed in subsequent cash crops.
• Warm up cold, mulched soil before transplanting tomatoes or peppers by digging the planting holes a day in advance and leaving them open to the sun.
• Bury sunn hemp seeds at least 1.5 inches deep with good seed-to-soil contact, as simply broadcasting the seeds on the surface will result in poor germination.